DOS

I am running milkit valves on my road tubeless wheels. They work fine for the most part, and its nice to be able to remove valve cores without air escaping tires. But I have had persistent problem where the valve core extender ((long black thing attached to core in the pic) gets stuck when removing cores, which eliminates the ability to add sealant with air still left in the tire, one of the main selling points of the valves. Is there some trick to getting the extenders to come out with the cores that I dont know about?

Crankycrank

I know nothing about these, but have you tried contacting milkit? FAQ - milkit.bike Click the dropdown "SUPPORT" link for a list of options

DOS

I have. They are sending me new cores, which is nice of them. But I dont think that is going to solve the issue. I have replaced cores before anly to have the problem repeat.